Population based screening is only recommended for colon cancer, breast cancer, cervical cancer, and liver cancer in Singapore. In the USA however, population based screening is also done for lung cancer as it has been shown to reduce risk of dying from it. Why then lung cancer screening has not been implemented in Singapore? To answer this question we need to know who fulfils the criteria for screening for lung cancer in the USA.
The people who should go for lung cancer screening based on USA based studies and guidelines are those who are 55 to 74 years old and currently smoke or have quit smoking in the past 15 years and have at least a 30 pack-year smoking history. (A pack-year is 1 pack of cigarettes per day per year. One pack per day for 30 years or 2 packs per day for 15 years would both be 30 pack-years). You can see the problem from here.
About 40% of lung cancer patients in Singapore are never smokers. If we were to use USA based lung cancer screening guidelines on our population, we will miss out this group of patients who have never touched a cigarette.
In addition, lung cancer has affected people as young as 31 year old in Singapore and hence the age criteria of the USA based guidelines cannot be applied to the population of Singapore. Due to differences in who and how lung cancer affects Asians versus western population, there is a need to come up with the lung cancer screening guidelines that are applicable to the local and regional population. This has not taken place yet.
What you can do? If you fall in the age group of 55 to 74 years old and currently smoke or have quit smoking in the past 15 years and have smoked 1 pack a day for 30 years or 2 packs a day for 15 years, you can go for an yearly low dose CT scan of the chest voluntarily. Low dose CT scan carries 5 times lesser radiation exposure than the traditional CT scan although the radiation exposure from a traditional CT scan is also much lower than the dangerous level of exposure.